NASHVILLE - Republican Gov. Bill Haslam continued to speak out Thursday against unionization of the Volkswagen assembly plant in Chattanooga, even as fellow GOP critic U.S. Sen. Bob Corker says further criticisms by him before next week's vote aren't appropriate.

Haslam's latest comments on the United Auto Workers union efforts came during a luncheon speech to the Tennessee Press Association. He touted Tennessee's attractiveness as a "right-to-work state" and criticized the union during a question-and-answer session.

"I've been fairly vocal in a way that some people have said, 'Why is it your business?'" Haslam told editors and publishers attending the TPA's winter meeting in Nashville. "I think it is our business in the state of Tennessee. We have a considerable investment in that plant. The state of Tennessee put a whole lot of money in that plant."

It has been reported that Tennessee put up nearly $600 million in incentives, or roughly $58,000 per job, to land the VW assembly plant.

Haslam also said "it's also an interest of ours because VW has been coming to us for a while" as the German auto manufacturer decides whether to put new car production in Chattanooga or in Mexico.

Earlier this week, Corker, a former Chattanooga mayor, said in a statement that he's holding his tongue on criticizing Volkswagen or UAW's organizing efforts until the election is held next week.

"During the next week and a half, while the decision is in the hands of the employees, I do not think it is appropriate for me to make additional public comment," Corker said earlier this week.

He has previously said Volkswagen would be a "laughingstock" if it becomes the first foreign-owned auto manufacturer to allow the UAW to find a toehold.

Corker helped recruit Volkswagen to Chattanooga. As a senator, he earned the enmity of UAW leaders when he heavily criticized the Obama administration's bailout of General Motors and Chrysler.

Asked about Corker's statements about withholding comment, Haslam repeated concerns that unionization would harm state efforts to lure more auto suppliers and other manufacturers to Tennessee.

"We're just saying what we've always said, that the state has a vested interest in this and I think -- from our viewpoint, from what we're hearing from other companies -- it matters what happens in that vote," he said. "I don't know that I'm trying to influence" the vote.

The three-day voting period by Volkswagen's more than 1,500 hourly workers begins Wednesday. The pending vote has taken on all the aspects of a tiny town election fracas as UAW officials and out-of-state conservative groups opposed to unions seek to sway plant workers.